Engine reversing-valve.



PATBNTBD MAR. s, 1908.

J.' G. PAIRBANKS. ENGINE RBVERSING VALVE.

APPLICATION FILED AUG. 12,-1907.

SHEETS-SHEET 1. l

dwong.;

4 No. 880,642. PATENTED MAR. `3, 190s.

J. G. FAIRBANKS.

ENGINE REVERSING VALVE.

APPLICATION FILED AUG. 12. 19M.

ZSHEETSSHEET 2.

C@ Y r l amm@ UNITED sTATEs PATENT oEEroE.

JAMES G. FAIRBANKS, OF MARION, OHIO.

ENGINE REVERSING-VALVE.

Speccaton of Letters Patent.

Patented March 3, 1908.

` Application filed August l2. 1907. Serial No. 388.246.

specification.

This invention relates to valves for steam engines and the like, and has for its principal object to provide valves of simple construction, whereby the direction of iiow of steam may be readily changed for the purpose of reversing the engine.

A further object of the invention is to provide controlling and reversing valves so arranged as to permit the use of ports or passages of short lengthand easy curvature, in order to prevent waste of steam and reduction of pressure.

A still further object of the invention is to provide a reversing valve disposed between the steam chest and the cylinder, and so constructed and arranged as not to impede the flow of steam, the valve being perfectly balanced, so that it may be easily moved when the direction of movement of the engine is to be reversed.

With these and other objects in view, as will more fully hereinafter appear, the invention consists in certain novel features of construction and arrangement of parts, hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims,it being understood that various changes in the form, proportions, size and minor details of the structure may be made without departing from the spirit or sacrificing any of the advantages of the invention.

n the accompanying drawings z-Figure 1 is a sectional elevation of a steam chest and portion of a cylinder provided with a valve constructed in accordance with the invention, the view being on the plane indicated by the line 1 1 of Fig. 5. Fig. 2 is asimilar view on the line 2-2 of Fig. 5. Fig. 3 is a detail perspective view of one of the valves, the top of the valve being cut away in order to show the interior construction. Fig. 4 is a detail perspective view looking from the bottom of the valve. Fig. 5 is a plan view with the top of the steam chest removed, one of the valves being, also, removed, in order to show the location of the ports. Fig. 6 is a transverse sectional .view on the line 6`6 of Fig. 5, the valves being removed. Fig. 7 is a sectional perspective view of the reversal valve, detached. A

y Similar numerals of reference are employed to indicate corresponding parts throughout ings.

The cylinder 10 may be of ordinary construction, and cast integral therewith is a steam chest 11 having a removable cap or cover 12. The bottom of the steam chest the several figures of the drawis formed by a horizontal partition 15 which v Q separates the chest proper from an inlet chamber 17 and an exhaust chamber 18, steam being supplied to the chamber 17 by a pipe 19, and the exhaust passing from the chamber 18 through a final port 20.

The engine shown in the accompanying drawing is of the twin cylinder or duplex type, and a single valve chest is employed on both engines. The steam enters the chest through passages 22 and escapes to the exhaust chamber 18 through ports 23. In the valve seat of the partition 15 are formed two ports 24 and 25 for each cylinder, the ports being in direct alinement transversely of its length, while the port 25 is in alinement with the exhaust port 23 in the direction of the length of the cylinder.

The casting below the partition l5 is bored out to form a cylindrical chamber for `the reception of a cylindrical reversing valve 26 and the ports 24 and 25 open into the top of this chamber. At the opposite sides of the reversing valve chamber are two cylinder ports 28, 29, these being so constructed as to form a single port at the point where it communicates with the cylinder, and divided to form a double port .corresponding to the ports 24 and 25 where it enters the reversing valve chamber.

The reversing valve 26 has two sets of ports, one set for each cylinder, and each set comprises a pair of curved ports 30-31, and a second pair of curved ports 32-33, the ports 30 and 31 coacting with the port 24, while the ports 32-33 coact with the port 25.

When the valve is in the position shown in Fig. 1, steam entering through the port 25 will pass through the porti33 to the cylinder port 28, and thence to the left hand end of the cylinder, while steam from the opposite `end of the cylinder will pass through port 29,

port 31 (Fig. 2) and port 24 to the exhaust. The ports 30 and 32 will be idle, their lower ends being blanked by the wall of the reversing valve chamber.

Arranged in the steam chest are two controlling valves of precisely the same construction. Each valve 40 is approximately rectangular in form -and is provided at one end with a socket 4l for the reception of the end of the actuating stem. rI`his valve has an exhaust port 42 that is in constant communication with the exhaust port 23 in all positions of the valve. The interior of the valve 40 is divided into three compartments or ports 44, 45 and 46, the port 46 being divided oil from the compartment 44 by means of a right angled partition 47 that extends from the top to the bottom of the valve. The top of the valve is closed at all points except to form a small port 48 that communicates with the compartment 46, and is designed in one position of the valve to permit the passage of steam through the port 24. rThe port or chamber 45 opens at one end of the valve, that is to say, the end opposite the valve stem, and is divided oil from the compartment 44 by a horizontal partition 50 and a vertical partition 51. The main compartment 44 communicates at one end with the.

exhaust port 42, and at the opposite end is provided with a port 52 (Figs. 4 and 5) to permit the passage of steam from the port 24 to the port 23.

In one position ci the controlling valve, (Fig. l), steam is entering the port 45, and passing through port 25 to one end of the cylmder, and is exhausting from the opposite end of the cylinder through the port 24 (Fig. 2), port 52, and compartment 44, port 42 and port 23. When the valve is in the opposite position, steam will enter through port 48 at the top of the valve compartment 46, port 24 to one end of the cylinder and exhaust from the opposite end of the cylinder directly through the compartment 44, port 42, and exhaust port 23.

When the engine is to be reversed, it is merely necessary to turn the valve 26 through an arc of ninety degrees, so that the previously inactive ports 30 and 32 will be placed in operative position, while the ports 31 and 33 will be rendered inoperative.

It will be observed that all of the ports or passages are short and of easy curvature, so that there will be no waste of steam and but little loss through friction.

I claim l. In combination, a cylinder, a steam chest, a pair of transverselyr alined steam ports leading from the valve seat of the chest to the cylinder, an exhaust port in the valve seat, the exhaust port being in alinement with one of the steam ports, and a slide valve having a pair of ports arranged to alternately open communication between the exhaust port of the valve seat and arranged to alternately communicate with said steam ports.

2. In an engine, a cylinder, a steam chest having a valve seat, a pair of cylinder ports opening in the valve seat in transverse alinement with each other, an exhaust port also formedin the valve seat, and a slide valve having an exhaust port in constant communication with the valve seat exhaust port and movable to alternately communicate with the cylinder ports, said valve being further provided with independent steam ports arranged to alternately communicate with their respective cylinder ports.

3. In a steam engine, a cylinder, a steam chest having a valve seat, cylinder ports opening into the valve seat in transverse alinement with each other, an exhaust port also formed in the valve seat in alinement with one of the cylinder ports in a direction lengthwise of the cylinder, a slide valve mounted on the seat, said valve being approximately rectangular in form and having integral partitions dividing the same into an exhaust port and a pair oi steam ports, the exhaust port being in constant communication with the exhaust port of the valve seat and arranged to alternately communicate with the cylinder ports, and the steam ports being arranged to alternately communicate with their respective cylinder ports.

4. In a steam engine, a cylinder, a steam chest having a valve seat, cylinder ports leading from the valve seat in transversely alinement to each other, said valve having also an exhaust port in longitudinal alinement with one of the cylinder ports, a rectangular slide valve mounted on the valve seat, partitions arranged within the valve and dividing the same into two steam inlet ports and one exhaust port, said exhaust port being in constant communication with the exhaust port of the valve seat and arranged to alternately communicate with the cylinder ports, one of said steam ports opening at the end of the valve for communication with the steam chest, and the Jfront of said ports opening at the top of the valve for communication with the steam chest.

5. In a steam engine, a cylinder, a steam chest, a controlling valve therein, a reversing valve chamber arranged between the steam chest and the cylinder, a pair of ports leading Jfrom the valve seat to the reversing valve chamber, ports leading from each end oi' the cylinder to the `reversing valve chamber and divided at the latter point into double ports, and a reversing valve arranged within the chamber and provided with ports spaced to correspond to the port openings in the chamber, said valve being circumferentially adjustable to reverse the direction of the iiow of the steam to and from the cylinder.

6. In a steam engine, a cylinder, a steam chest", a controlling valve therein, a reversing valve chamber between the steam chest and the cylinder, a pair of ports leading from the valve seat to the upper portion of the reversing valve chamber, a pair of ports leading from each side of the reversing valve chaml In testimony' that I claim the foregoing as ber to the ends of the cylinder, and a oylinmy own, I have hereto aihxed my signature drieal reversing valve disposed Within said in the presence of tWo Witnesses.

chamber, said valve having ports spaced JAMES G. FAIRBANKS. 5 approximately at ninety degrees from each I/Vitnesses:

other and arranged to direct the steam to and C. W. FAIRBANKS,

from either end of the cylinder. R. C. MCCOLLUM. 

